Fhrx

The two main issues faced by high power audio systems these days are power delivery (including earthing) and power storage (including batteries and capacitors). 1. Power delivery. In a DC system you need to make sure your cables are of adequate size and that all the earths have been upgraded accordingly. Electrons will not leave the negative terminal if they cannot flow back to the positive. Therefore the cables should be the first angle of attack. 2. Power storage. The main fundamental difference between high quality batteries and capacitors is that batteries generate charge from a chemical reaction whereas capacitors simply store charge. Both can discharge quite fast (although the cap is fastest), both can smooth out voltage, both can supply plenty of power to your amplifier when its needed however the battery is generally the cheaper option and indeed the one we recommend first. The battery will also hold more reserve charge too allowing you to run your system for longer when the car is not running. The short conclusion; get a quality deep cycle battery and make sure the cables are adequate. That should provide your system with enough power taking into consideration the scenario you have listed above.

For a single 12" subwoofer you'll want the wall thickness to be between 6mm and 12mm depending on how many bends, strengthening ridges etc are in it. When constructing fibreglass enclosures here we utilise an extremely sophisticated testing procedure to see if the enclosure is strong enough. I put them on the ground and jump on them. If the wall flexes at all then it is not strong enough.

We tend to run an earthing kit at the front of the car which makes the cars body a much stronger earth. We then earth the amplifiers at different points to allow more current to flow across the threads...

If you're looking to see someone on the north shore then give Hutch at Metrosound a try. Hutch (Metrosound) 79 Whiting street, Artarmon Tel: (+61 2 ) 9436 1995 Fax: (+61 2) 9436 4996 E-mail: [email protected]

Well you cannot argue with the mans honesty. Ha-ha!

Yo George, I was having a browse through your website last night while waiting for my FTP server to finish. You're getting quite a gallery full of nice installs there. You should get a group together and head up for the next round!

Vijay, you should have come down dude.

You might want to read the rules Chris. Just to improve that knowledge of yours. I'm not allowed to judge my class. Which I don't. Was it really interesting to you mate? Or were you actually just replying with a totally unhelpful comment in an attempt to bring our reputation into disrepute?

Just in relation to amplifiers; why stop at those three brands? Some other brands I would recommend adding to your audition list (do still include those three too) include: Audio System Audison Diamond Audio Boston DLS Crossfire Infinity Phoenix Gold Treo ARC Audio Zapco Tru-Tech Milbert Blaupunkt Digital Designs Vibe Earthquake Check them all out before making a choice. Remember there are a lot more brands out there - you shouldn't necessarily choose a mainstream one based solely on the size of their marketing campaign. If you need to know what specs to look for when chosing an amplifier, click here.

To be honest I haven't experimented beyond two channel audio. I'm not sure what the amplifier would do if you feed it a 5.1 music format. It only has a two channel slave output though so you could not run another bunch of amplifiers for surround, center and subwoofer channels. They retail at $2999.

Should have some around here somewhere. Shoot me an email if you want me to send them to you.

We often use the Focal Dual Monitor amplifier (it has inbuilt DSP etc) as a master and the Focal FP1.800 as a slave. However the output from master to slave is analogue (RCA). It is an optical input to the DM though. Click here for more information.

We were doing Nuvotech carputers but we've just started doing Phoenix Smart Navi units. The link to their website is here. They have assured me there will be more information and better images up on thier website soon.

Here is an example of where we install 10" subwoofers:

What you should do is fully sound deaden the front doors, both on the inner and outer skin. Once that is done then install diffusers and make up baffles to run 6.5" drivers. Chris can do all this for you if you're up in his neck of the woods. The R33 Skyline doors look like this when done. I know it's not an R34 but it gives you an general idea of what I'm talking about. Well, that is how we do them anyway.

They're a 6" in the front but with a 'rounded off square' template... If you know what I mean?

We usually just make up an plastic surround.

Is there a reason you wish to upgrade the rears? Seeing as you sit at the front and your ears face forwards I'd concentrate on the front speakers and perhaps some sound deadening for your front doors.

Really?

Your ideas for the system are correct. Most high quality SQ systems simply have a set of splits in the front, a single subwoofer in the rear and a nice powerful amplifier to run them. We quite often employ amplifers like the Audison SRx3 to run systems just like yours.

Quick question; what state are you located in champ?

Guys' we constantly get asked "Where should I place my tweeters for best performance?" This is our standard reply: Okay, lets all think about staging for a second. You don't go to a concert and sit with your back towards the band right? And admit it - we'd all like to be right in front and center of the band on stage true? And you'd also like to be at the right height to - like you were on the actual stage right in front of them listening. This is the imaginary image we try and capture inside cars today when we position tweeters in vehicles. Getting this is not just a simple matter of slapping them in just anywhere either. The problem with mounting tweeters up high (e.g. on the sail area on the door) is this: Think about the position of your ears in relation to the tweeters. One speaker is belting the high pitch tunes out about two feet from your right ear where as the left tweeter is triple that distance away. The stage has no choice but to be right out the right window. Sheer laws of physics govern this fact. Now if you place the tweeters down in the kick panels then the right speaker distance is about three feet and the left speaker is about three and a half. The problem is not eradicated but it becomes a lot less noticeable as the distance separation is reduced. Now obviously the tweeters cannot be placed anywhere where they fire straight into ones feet so you have to be very careful about their placement on both sides and the more often than not this results in them being mounted very high in the kick panel, quite often out of sight like mine are because they're so far up under the dash. The next question people ask is this; isn't the stage going to be low? The answer is not so much to do with the physical tweeter location but the power level they receive. If you have sufficient power going to each tweeter from a high quality amplifier then your tweeters will not only fill out the stage 'height' nicely but the entire front cabin of the car. That said though, serious competitors utilise ambient tweeters up high (these are much quieter than the primary tweeters however) to lift the stage a little to head height from chest height that usually exists. And someone is bound to mention time alignment - they always do. The biggest problem with time alignment is this; the better you make your side sound (and you can get it absolutely perfect), the more your passenger suffers. Think about it - it time delays the right side speaker so both signal paths reach your ears at the same time. The problem is that the passenger has the reverse problem to you so as you side gets closer to being the same side to side, theirs get worse and worse. So how does one get the stage right in real world terms? At the end of the day you just have to play around a bit (and sometimes it can take up to four hours or so) to get the tweeter placement just right to achieve a nice stage 'width' , 'height' and 'depth'. Get yourself a nice big blob of blue-tac. Stick the tweeter onto a panel somewhere and grab a song with powerful female vocals (a strong female voice is generally considered best for stage testing). Close your eyes and imagine you're at the concert. Now listen to where she is coming from. Is she singing right in front of you? Is she off to the left a tad or right? Simple move the tweeter a few inches in a direction and have another listen. How is the image? Can you hear where all the band members are exactly? How is the depth? Does the drummer sound like he is behind the other musicians? Keep doing this until you get the image dead center or just off to the left a little bit but remember to take a rest every fifteen minutes to let your ears normalize. If you attempt staging for hours your ears tend to 'hallucinate' and give false readings.

Amen bro!

No no, just didn't list every brand I could think of. There is a good 500 odd other brands I could add too.

Both Tony (Doran) and us (Fhrx Studios) are having an unsanctioned CAASQ / dBDrag event on July 23rd. More details can be found on Car Audio Australia.